/*
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *    ExtensionFileFilter.java
 *    Copyright (C) 1999 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.gui;

import java.io.File;
import java.io.Serializable;
import java.io.FilenameFilter;
import javax.swing.filechooser.FileFilter;

/**
 * Provides a file filter for FileChoosers that accepts or rejects files based
 * on their extension. Compatible with both java.io.FilenameFilter and
 * javax.swing.filechooser.FileFilter (why there are two I have no idea).
 * 
 * @author Len Trigg (trigg@cs.waikato.ac.nz)
 * @version $Revision: 1.8 $
 */
public class ExtensionFileFilter extends FileFilter implements FilenameFilter,
		Serializable {

	/** The text description of the types of files accepted */
	protected String m_Description;

	/** The filename extensions of accepted files */
	protected String[] m_Extension;

	/**
	 * Creates the ExtensionFileFilter
	 * 
	 * @param extension
	 *            the extension of accepted files.
	 * @param description
	 *            a text description of accepted files.
	 */
	public ExtensionFileFilter(String extension, String description) {
		m_Extension = new String[1];
		m_Extension[0] = extension;
		m_Description = description;
	}

	/**
	 * Creates an ExtensionFileFilter that accepts files that have any of the
	 * extensions contained in the supplied array.
	 * 
	 * @param extensions
	 *            an array of acceptable file extensions (as Strings).
	 * @param description
	 *            a text description of accepted files.
	 */
	public ExtensionFileFilter(String[] extensions, String description) {
		m_Extension = extensions;
		m_Description = description;
	}

	/**
	 * Gets the description of accepted files.
	 * 
	 * @return the description.
	 */
	public String getDescription() {

		return m_Description;
	}

	/**
	 * Returns a copy of the acceptable extensions.
	 * 
	 * @return the accepted extensions
	 */
	public String[] getExtensions() {
		return (String[]) m_Extension.clone();
	}

	/**
	 * Returns true if the supplied file should be accepted (i.e.: if it has the
	 * required extension or is a directory).
	 * 
	 * @param file
	 *            the file of interest.
	 * @return true if the file is accepted by the filter.
	 */
	public boolean accept(File file) {

		String name = file.getName().toLowerCase();
		if (file.isDirectory()) {
			return true;
		}
		for (int i = 0; i < m_Extension.length; i++) {
			if (name.endsWith(m_Extension[i])) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Returns true if the file in the given directory with the given name
	 * should be accepted.
	 * 
	 * @param dir
	 *            the directory where the file resides.
	 * @param name
	 *            the name of the file.
	 * @return true if the file is accepted.
	 */
	public boolean accept(File dir, String name) {
		return accept(new File(dir, name));
	}
}
